Elevator bomb rack for aeroplanes



Dec. 6, 1932.

R.- BOLLAM ELEVATOR BOMB RACK FOR AEROPLANES File d June 13.

1931 4 Sheets-Sheet l INVENTOR Richard E. Bollam ORNEY M76, 1932. R. E. BOLLAM ELEVATOR BOMB RACK FOR AEROPLANES Filed June 13. 1931 4 Sheets-Sheet 2 INVENTOR Richard E. Bollam TTORNEY R E. BOLLAM 1,898,142

ELEVATOR BOMB RACK FOR AEROPLANES Filed June 15. 1931 4 sheets -sheet 5 IINVENTOR Rchard E.BoHam Dec. 6, 1932. R. E. BlOLLAM 1,89@,142

ELEVATOR BOMB RACK FOR AEROPLANES Filed June. 13. 1931 4 Sheets-Sheet 4- Ric y ll am ATTORNEY Patented Dec. 6, 1932 RICHARD E. BOLLAM, F PORTLAND, OREGON ELEVATOR BOMB RACK FOR AEROPLANES Application filed June 13,

My invention relates to aircraft and, more particularly, to military types, which carry more or less heavy bombs on the under side of the fuselage, which bombs are released a computed distance in advance of the ob]ect to be struck. Experience with planes having machine guns mounted thereon has taught that excellent aim can be secured by arranging the rifle barrel in axial alinement w1th that of the plane and aiming the plane itself at the object to be struck. It is impractical to arrange the bombs in fixed position beneath the fuselage, so that the latter can be released in a vertical diving flight, because the bombs necessarily have to pass thru the area traversed by the propeller blades.

The object of my invention is to provide an elevatingrack for bombs of this character, which rack is adapted to lower the bombs a sufiicient distance below the fuselage and the path of the propeller blades so that the bomb can be released in a vertical dive of the aeroplane and thus the bombs can be released directly above the object to be struck. This eliminates the necessity for computing flying speed, elevation, and other disturbing factors which produce a horizontally-curved bomb flight trajectory as when bombs are released during horizontal aeroplane flight.

A bombing aeroplane with the bombs suspended beneath the plane has further disadvantages, one that the presence of the bomb is obvious and deception as to its character is impractical. This permits enemy gun fire and hostile aeroplane to center the r attack upon such bomb carrier. Further, the wind resistance of an aeroplane with the bomb suspended in this manner is substantially increased and experience has taught me that the placing of a bomb on the exterior of the fuselage decreases the operating speed three to eight per cent.

The large mass arranged eccentrically with respect to the longitudinal axis of mass of the plane further retards maneuverability to evade hostile attack and enemy gun fire and a further object of my invention, therefore, is to so arrange the elevating mechanism for the bomb rack so that the rack and bomb carried thereby can be wholly housed Within Cal 1931. Serial No. 544,051.

the fuselage at all times, except when the bomb is arranged for release. The rack and its load are further positioned with respect to the longitudinal axis of mass of the aeroplane, so that such additional mass is centered, more or less, about such axis to increase maneuverability. Inasmuch as the bomb itself represents a substantial amount of added weight which must thus be centered, I arrange a plurality of stations spaced with respect to such axis of mass of the aeroplane and provide automatic means for stopping the rack when loaded at a diflerent station than when it is empty. Thus the disposition of such mass about said axis is variable to produce centralized mass during both'loaded or unloaded conditions of said rack.

In order to maintain stream-line contour to the fuselage, I provide doors adapted to close the opening thru which said rack ascends and descends, the exterior of such door following the stream-line contour of the plane. The door in opening preferably moves laterally outwardly in the walls of the fuselage, so as to add no interfering agency to flying speed and the bomb rack is provided with a dummy door adapted to fit tightly within the opening when the rack is fully extended, so as further to maintain such flying contour of the fuselage.

A further object of my invention is to provide a device of this character which is strong, rugged and reliable in action, one which is provided with suitable and complete indicators, manual and electric operating and control devices to minimize failure of action and the whole structure is designed to minimize weight to maintain high flying speed of the aeroplane.

The details of my invention are hereinafter described with reference to the accompanying drawings, in which:

Fig. 1 is a longitudinal elevation of an aeroplane with portions of the fuselage shown broken away to disclose the movable elevating bomb rack located therein, such figure further showing the position of the bomb in dotted lines and with respect to the propeller blades, as when such bomb is arranged in extended or lowered position;

thru such bomb rack and elevating mechanism taken substantially on the line 44 in Fig. 3;

Fig. 5 is a transverse vertical section taken substantially on the line 55 in Fig. 3; and

Fig. 6 is a diagrammatic layout of the electrical connections of the mechanism.

My invention is particularly adapted to be embodied in an aeroplane of the bomber type when adapted for heavy projectiles and of correspondingly lighter type with lighter type projectiles. The type or form of such aeroplane plays'little or no importance with regardto my specific invention and thus the detlails will not be described with greater detai My invention is preferably embodied in an aeroplane (I. having a substantially continuous'fuslage and, at the forward end, a propeller b. Extending downwardly from the under surface of the fuselage is landing gear 0, shown as wheels asfor use on land planes. Housed within such fuselage is elevating mechanism for a bomb d, which elevating mechanism is mounted within a series of vertical members 6 arranged in pairs and at opposite sides of the plane.

Extending between such pairs of supporting members 6 is a horizontally-arranged spider f, carried by spaced lead screws f mounted in bearings f2 in horizontal members 6 forming part of the supporting frame thereof. Such feed screws are preferably arranged at the four corners of the spider and also at the middle of such spider, as is shown in Fig. 3. The operating mechanism is driven by a generator, storage battery, or some other source or'accumulator of electricity, shown diagrammatically in Fig. 6 as a battery 9.

The mechanism is driven by an electric motor k, which powers the shaft h extending longitudinally of such elevating mechanism. Such shaft is connected by three transverse shafts i to the lead screws f. The connection is preferably made thru sets of worms and worm gears z". Inasmuch as -a single motor drives the shaft h and therewith all of the transverse shafts z', the lead screws f are operated synchronously and thus the spider is fed vertically, uniformly, and tends to be maintained in a horizontal plane. When I speak of vertical and horizontal planes, I mean to describe the position of objects when the aeroplane isflying in a horizontal plane, or is at rest.

The bomb d is carried between a pair of saddle-like receivers 7', depending from the under side of the spider f. The bomb d is provided with a. series of pockets, properly spaced with respect to such receivers, and pins engage said pockets and hold the bomb in position during flight. Such pins k are retractable and each is operated by a bellcrank lever Z, mounted upon a pivot pin 1, and a pull rod m pivotally engages the bell crank at point m. Such pull rods are moved longitudinally by forks m2 fixed to a trans- 'verse rock shaft m3.

The releasable pins 70 are arranged in two sets, one set at the forward end of the bomb and the other towards the rear end thereof. Because the operating mechanism for each set is the same, I have shown in Figs. 3, 4, and 5 the operating mechanism for only one set and it is to be understood that the structure and operation of the other set is identical withthe one described. Both sets of operating mechanisms are driven from a common shaft m4, which extends longitudinally of the spider and said longitudinal .shaft drives spaced laterally-arranged shafts m5 thru the medium of worms and worm gearing m6. Such shaft m4 is driven by an electric motor m7 carried by the spider, as is shown in Figs. 3 and 4.

Beneath the bomb-elevating mechanism the fuselage is provided with an opening closed by a door comprising a pair of sliding panels 01., which move in guides 0, 0" and 02, being extensible laterally of the plane in such guides. Such pair of panels 'n abut substantially on the median line thru the center of the elevating rack, as is shown in- Fig. 5. Such panels are moved outwardly by rack p and pinion 1- mechanism, as is shown in Fig. 3. Two sets of rack and pinion mechanisms are provided, one arranged at each end of the bomb-elevating chamber, but in Fig. 3 the mechanism for one end only is shown, for the reason that these sets of mechanisms also are duplicates of each other. The pinions r are mounted upon longitudinal shafts 1*, which extend the full length of the frame and thus all four pinions are operated in synchronism. Said shafts r are driven by the motor 8, (see Fig. 6).

In addition to the electric drive for such rack operating mechanism, and for such door-closing mechanism, I have provided a hand wheel b2 extending within the cockpit of the aeroplane, by which the operator can manually operate the bomb-elevating mechanism. Also extending into such cockpit is a hand mechanism comprising a lever r2 capable of operating the shaft and gearing 18,

the shafts 'r, and thus the rack and pinion mechanisms 12 and 1', respectively.

The mechanism of the devices is best explained with reference to the electrical diagram, Fig. 6, and many of the parts referred to in the electrical diagram are not shown in the disclosure of the physical apparatus and with regard to the physical construction of the remaining apparatus, because no advantage of clarity would be attained by the position and proportion of the physical elements.

As has been pointed out heretofore, the entire electrical system is shown as receiving its power from a source or accumulator of electrical energy, shown as a storage battery g. The main power line 9 leads therefrom thru three branches, g2, g3 and g4. Arranged in such branches, respectively, are distantly-actuated controls t, t and 252. The control t makes and breaks the branch circuit 92 leading to the bomb elevator motor h. The control t makes and breaks the branch 93 leading to the bomb releasing and securing motor m7 and the control t2 makes and breaks the branch 94 leading to the door control motor s.

Each of such motors and controls are distantly operated thru auxiliary electric circuits and thus adapted for push-button control. The push button u closes the auxiliary control circuit u, which causes the 'motor h to elevate, or retract the bomb rack into the fuselage. Such push button further makes the auxiliary control circuit 102 for the closing solenoid a3, which forms a part of the control t3 and closes the main service switch-'2) in the feed circuit 9'. In other words, when the push button at is depressed, it also closes an auxiliary circuit having electro-magnetic devices 143 arranged therein, which latter are adapted to close the main control switch 25 and thus to energize the entire electrical system.

The push-button control 107 functions in one particular in a manner similar to the pushbutton control a, inasmuch'as it makes the .auxiliary circuit a2 to energize the solenoid a8 and thus to close or make the main control switch '0. It only indirectly starts the elevator mechanism downwardly. The closing of the push-button control 117 makes the auxiliary control circuit n8, which energizes the left-hand solenoid of the control 252 to move the switch elements of such latter control to the position shown in Fig. 6, and to cause the door-opening motor 8 to function to open the doors 91. When such doors or move to their full open position, they close the switch 1014, which is normally open, and the closing of such switch 209 makes the auxiliary control circuit U15, which energizes the left-handsolenoid of the control t to move the switch element to the position shown in Fig. 6., The moving of such switch elements to such latter position closes the operating circuit for the rack-opening motor h, which causes the latter to lower the bomb rack.

Arranged at the upper limit of travel of the elevator is a limit switch a9, which opens the rack motor circuit when the rack elevator reaches its upper limit. Similarly arranged and having a similar function is a limit switch ulO arranged at the lower limit the elevator and their physical characteristics are not further described or shown and need no further explanation.

The limit switch all is shown in Figs. 3 and 4 in connection with auxiliary operating mechanism. It is essential that the elevator mechanism be not stopped when the bomb is in position and carried by such mechanism, until such mechanism has reached its upper limit of travel. To accomplish this result, I arrange a bar :11, as is shown in Fig. 3, transversely of the spider and adapted for lateral reciprocation therein. A rack m is cut from the upper face of such member and a pinion m2 is carried by the shaft m4 and engages such rack. The other end m3 of the member a: is flattened and is adapted to engage with the switch ull arranged at one side of the spider and carried by one of the fixed structural members. With the member 00 positioned as shown in Fig. 3, the end :03 will come in contact with the operating member of the switch all when the bomb support passes the horizontal plane of the'door n and the rack-operating mechanism will be stopped. With the member m fully retracted, that is, moved upwardly as shown in Fig. 3, said member 00 will clear the switch all and will not thus actuate the latter.

As has been described heretofore, it is necessary that the motor m7 be operated to fix the pins kin the bomb d and the shaft m4 serves as the common physical agency for transmitting the power from the motor m7 to the rods m for retracting the pins in. The pinion m2 is mounted upon such shaft m4 and the parts are arranged so that with the pins k in releasing position the latter will not hold a bomb in place and the member a: will be arranged to engage the switch all. With the pins 70 arranged in engaging position so as to hold a bomb, the member a: will be thrown by the same operating mechanism into disengaging position with respect to the switch all. The result, therefore, is that the elevator mechanism will be stopped on elevator mechanism.

its upstroke when empty at a point intermediate its upper and lower limits and will be stopped when loaded with a bomb only at its upper limit of travel.

Located physically adjacent the switch all in the bomb rack operating circuit is a switch u12 in the auxiliary control circuit @013, which latter switch is normally open. When the rack-elevating mechanism moves upwardly past the position of the switch all, it closes such switch @012, which makes the circuit @013, energizes the right-hand solenoid of the control t2, moves the switch element of the latter to a position opposite to the position of the switch element as shown in Fig. 6, and energizes the door-operating motor 8 in such a manner as to cause the door a to close.

If the ascending rack mechanism does not contain abomb it stops at such point and sufiicient clearance is allowed to permit the doors to close. If the rack holds or carries a bomb, the rack continues to ascend upwardly and a suflicient time interval is permitted to elapse to permit the doors to close beneath such ascending bomb. The provision and the location of such switch @612 prevents the closing of the doors at when any portion of the bomb rack is below the horizontal plane of the doors, for the reason that such switch u12 is operated by the rack passing the point noted. A similar safety provision is provided in the operating circuit for the motor m7 by a switch 1 which switch is located adjacent the lower limit switch ulO, for the rack Such circuit forthe motor m7 is held open so that the bomb cannot be released except when it is in its lowered position.

The push-button control w controls the auxiliary circuit w, which latter circuit en ergizes the right-hand solenoid in the control t and thus to arrange the switch element '02 of such control in the opposite position to which it is shown in Fig. 6, such pushbutton control w must be closed. In the electrical circuit controlling the operation of the bomb motor m7 in such a manner as to move the pins is toward the bomb and into engagement therewith, a limit switch 204 is provided for the motor m7, which switch w t is opened when the pins arefully in engaging position, such switch also normally being closed. The pins are retracted and the bomb is released by the closing of the pushbutton control @122, which closes the auxiliary circuit 103 and energizes the left-hand solenoid of the control t to move the switch element o2 to the position shown in Fig. 6.

The operating circuit for the motor m7 for releasing such bomb includes the switch y heretofore described, and when such switch is closed by the lowering of the rack mechanism to its lower limit, the motor m7 can be energized to retract those pins by the actuation of the push button 102. A limit switch elements of the operating mechanism. Al-

though the three operating mechanisms, namely the rack-operating mechanism, the door-operating mechanism and the bomb-releasing and securing mechanism are powered by separate motors, the contacts are arranged as has heretofore been explained, so that control can be secured by five buttons and one of such buttons is merely an auxiliary stop button which breaks the electrical circuit for all of the devices.

Carried on the under side of the spider fis a dummy door 2, which is adapted to engage with the sides of the opening normally closed by the floor panels m and toseal said opening when the rack mechanism is extended or lowered to its limit. Said dummy door 2 thus seals said opening during flight with the bomb extended to maintain the. streamline contour of the fuselage.

I claim:

1. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack, laterally stable elevator mechanism for such rack adapted tomove the latter within limits and the lower or extended limit positioning the bomb beyond a such rack adapted to move the latter within limits, the lower or extended limit position ing the bomb outside of the fuselage and beyond a prolongation rearwardly of the operating area of the propeller.-

3. In an aeroplane provided with a lon tudinally-extendin-g fuselage, a propelle alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, laterally stable elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage and beyond a prolongation rearwardl of the operating area of the propeller.

4. Iii an aeroplane provided with a longitudinall -extending fuselage thru which the longitu inal axis of mass of said aeroplane extends, a propeller alined with the said fusela e and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-sect on of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage and with the longitudinal axis of mass of said rack, elevating mechanism, and bomb approaching the similar axis of the aeroplane, the lower or extended limit positioning the bomb outside of the fuselage and beyond a prolongation rearwardly of the operating area of the propeller.

5. In an aeroplane rovided with a longi-.

tudinally-extendin uselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an openin extending thru said fuselage, elevator mec anism for such rack adapted to move the latter within limits, the upper or retract ed limit positioning the bomb within said fuselage, and with the longitudinal axis of mass of said rack, elevating mechanism, an d bomb approaching the similar axis of the aeroplane, the lower or extended limit positioning the bomb outside of the fuselage and beyond a prolongation rearwardly of the operating area of the propeller, and means for positioning the rack at one of a plurality of stations spaced laterally with respect to said longitudinal axis of mass of the aeroplane.

6. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the with an opening extendingthru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the

upper or retracted limit positioning the bomb within said fuselage, and with the lontudinal axis of mass of said rack, elevatmg mechanism, and bomb approaching the similar axis of the aeroplane the lower or extended limit positioning the bomb outside peller, and automatic means for ositioning the rack at one of a plurality of stations spaced laterally with respect to said longitudinal axis of mass of the aeroplane.

7 In an aeroplane provided with a longigitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage and means adapted to close the opening in the fuselage.

8. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and-mounted at the forward end thereof, and. operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, ,elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage and a door adapted to close the opening in the fuselage.

9. In an aeroplane rovided with a longitudinally-extending uselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, .the lower or extended limit positioning the bomb outside of the fuselage and a; door consisting of two oppositely movable halves adapted to close the opening in the fuselage.

10. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mountedvwithin such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage, means adapted to close the opening in the fuselage and means synchronized with said elevator mechanism for operating said means with relation to the operation of said elevator mechanism.

11. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alin ement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage, a door adapted to close the opening in the fuselage and means synchronized with said elevator mechanism for operating said door with relation to the operation of said elevator mechanism.

12. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage, means adapted to close the opening in the fuselage and a sealing member adapted to seal said opening when the rack is extended to its lower limit.

13. In an aeroplane rovid ed with a longitudinally-extending uselage, a propeller alined with the saidfuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage, means adapted to close the opening in the fuselage and a sealing member operated by the elevator mechanism adapted to seal said opening when the rack is extended to its lower limit. I

14. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extendingthru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage, the lower or extended limit positioning the bomb outside of the fuselage, said rack and elevator mechanism comprising a plurality of lead screws extending transversely of the fuselage, a spider element carried thereby, a bomb support depending from said spider element, releasable bomb-securing retracted limit positioning the bomb within said fuselage, the lower extended limit positioning the bomb outside of the fuselage, said rack and elevator mechanism comprising a plurality of lead screws extending transversely of the fuselage, a spider element carried thereby, abomb support depending from said spider element, releasable bomb-securing means associated with the latter, said securing means'comprising a pin movably secured to said support and distant operating means for moving said pin into and out of bombengaging position.

In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantially greater diameter than that of the cros -section of the fuseversely of the fuselage, a spider element car ried thereby, a bomb support depending from said spider element, releasable bomb-secur- .bomb within said fuselage,

ing means associated with the latter, said securing means comprising a plurality of retractable pins movably secured to said suport.

p 17. In an aeroplane provided with a longitudinally-extending fuselage, a propeller alined with the said fuselage and mounted at the forward end thereof, and operating in a circular area of substantiallygreater diameter than that of the cross-section of the fuselage, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuselage, elevator mechanism for such rackadapted to move the latter within limits, the upper or retracted limit positioning the the lower or extended limit positioning the bomb outside of the fuselage, said rack and elevator mechanism comprising a plurality of lead screws extending transversely of the fuselage, a spider element carried thereby, a bomb supportdepending from said spider element, releasable bomb-securing means associated with the latter, said securing means comprising a plurality of retractable pins movably secured to said support and distant operat ing means for movin said pins simultaneously into and out 'o bomb-engaging position.

18. In an aeroplane provided with 9. Iongitudinally-extending fuselage thru which the longitudinal axis of mass of'said aeroplane extends, a propeller alined with the said fuselage and mounted at the forward end thereof, and operatin in a circular area of substantially greater 'ameter than that of the cross-section of the fuselage, a. bomb rack mounted within such fuselage, above and in vertical alinement with an'opening extending thru said fuselage, elevator mechanism for such rack adapted to move the latter within limits, the upper or retracted limit positioning the bomb within said fuselage and with the longitudinal axis of mass of said rack, elevating mechanism, and bomb approaching the similar axis of. the aeroplane, the lower or extended limit positioning the bomb outside of the fuselage and beyond a prolongation rearwardly of the operating area of the propeller, said rack and elevator mechanism comprising a plurality of lead screws extending transversel of the fuselage, a spider element carried t ereby, a. saddle-like bomb support depending from 4 said spider element, releasable bomb-securing means associated with the latter, said securin means comprising a plurality of retracta le pins movably secured to said support, distant operating means for moving said pins simultaneously into and out of bomb-engaging position, a door consisting of two oppositely movable halves adapted to close the opening in the fuselage, means synchronized with said elevator mechanism for operating said door with relation to the operation of said elevator mechanism, a sealing member operated by the elevator mechanism and carried by said spider adapted to seal said opening when the rack is extended to its lower limit.

19. In an aeroplane provided with a longitudinally-extending fuselage, a bomb rack,

laterally stable elevator mechanism for such rack adapted to move the latter within limits and the upper or retracted limit positioning the bomb within said fuselage.

20. In an aeroplane provided with a longitudinally-extending fuselage thru which the longitudinal axis of mass of said aeroplane extends, a bomb rack mounted within such fuselage, above and in vertical alinement with an opening extending thru said fuse- In testimony whereof he has aflixed his signature.

RICHARD E. BOLLAM. 

